Metal detector



FIG. 1 is a perspective view of a metal detector showing the claimed design;

FIG. 2 is a top plan view thereof;

FIG. 3 is a rear elevational view thereof;

FIG. 4 is a bottom plan view thereof;

FIG. 5 is a right side view thereof;

FIG. 6 is a front elevational view thereof; and,

FIG. 7 is a left side view thereof.

The broken lines depict portions of the design that form no part of the claimed design. 

CLAIM The ornamental design for a metal detector, as shown and described. 